Recent Advertisement Click Counts
Amazon● MediumFULLTIMEPHONE SCREENProblem statement
You receive a finite sequence of advertisement click and count operations. Each operation is one of:
CLICK <adId> <timestamp>: record one click for the advertisement.COUNT <adId> <timestamp>: report how many clicks that advertisement received during the latestkMinutes.
Timestamps are integer seconds and never decrease. Process operations in input order, including operations with the same timestamp. For a count at time t, include clicks whose timestamps are in the inclusive interval [t - 60 * kMinutes + 1, t].
Return one integer for each COUNT operation, in query order. CLICK operations produce no output.
Function
countRecentAdClicks(operations: String[], kMinutes: int) → int[]Examples
Example 1
operations = ["CLICK shoes 100","CLICK books 120","CLICK shoes 159","COUNT shoes 160","COUNT books 180","COUNT shoes 220"]kMinutes = 1return = [1,0,0]At time 160, only the shoes click at 159 remains in [101,160]. The books click at 120 is outside [121,180], and both shoes clicks are outside [161,220].
Example 2
operations = ["CLICK ad1 10","CLICK ad1 69","COUNT ad1 69","COUNT ad1 70"]kMinutes = 1return = [2,1]At time 69, timestamp 10 is exactly the inclusive lower boundary. At time 70, the lower boundary advances to 11, so only the click at 69 remains.
Constraints
1 <= operations.length <= 100000.1 <= kMinutes <= 100000.- Every operation is exactly
CLICK <adId> <timestamp>orCOUNT <adId> <timestamp>, with single spaces between tokens. - Each advertisement ID contains 1 to 50 lowercase English letters or digits.
0 <= timestamp <= 10^12, and timestamps are nondecreasing.- Use signed 64-bit arithmetic for timestamps and window boundaries.